1. Field of the Invention
The present invention relates to a crossbow device, and especially relates to a device capable for shooting a projectile (such as arrow) in the steadiest and most accurate means and assembling and disassembling more convenient.
2. Description of Related Art
Bow is an object with killability and amusements and gradually progress from killing to the athletic items (the archery). The archery needs extreme concentration, applied skills of wrists and arms, and stability of feet. It really a good traditional exercise for physically and mentally training. There are two kinds of bow, one is archery shooter bow with half-moon shape and the other is crossbow with gun shape. They are different in use. The bow with half-moon shape must be pulled by two arms with large power and then the projectile (arrow) is shot by the elastic force. The crossbow is launched as gun and the projectile is shot only by fingers to pull the trigger to shoot the projectile. Although there are differences in shooting, the same thing is that users must stand stably, keep two arm balance and steady, and be skilled in fingers and wrists. Therefore, the projectile may be shot steady and smoothly and keep accuracy and stability. The crossbow needs more skills to accurately shoot.
Please refer to FIGS. 5 and 6, the conventional crossbow includes a bow body 10, a bow rod 20, and a bow string 30. An installed groove 101 is concavely arranged at a top end of the bow body 10 and one end thereof is open.
The installed groove 101 is slid in one end of the bow rod 20 and partially exposed to the bow body 10. A sliding groove 201 is laterally cut at the end of the bow rod 20 exposed to the bow body 10 and divided the bow rod 20 to an upper rod portion 202 and a lower rod portion 203. A bolt 40 is arranged at the end of the lower rod portion 203.
The bow string 30 is arranged at the end of the bow rod 20 exposed to the bow body 10 and against the side of the bow rod 20 with the bolt 40. A screw 50 is passed through the bow string 30 and then screwed with the bolt 40 so as to fasten the bow string 30 to the bow rod 20. The above mentioned structure is the conventional crossbow.
In order to reduce the weight of the crossbow, the bow rod 20 is mostly made by plastic materials because the metal bow rod 20 is too heavy to hold and aim stably. But, if the bow rod 20 is made by plastic materials, the bolt 40 is impossibly made by plastic materials because the bolt 40 needs to cooperate with the metal screw 50. There are many drawbacks describe as below.
Firstly, it is not easy to fasten the metal bolt 40 to the plastic bow rod 20. If the metal bolt 40 is fastened to the plastic bow rod 20, it is easy to make the bow rod 20 crack.
Secondly, if it made by inert molding, the cost will be increased and the insert part is easy to be damaged.
Thirdly, before shooting, the projectile is arranged on the slot 204 of the bow rod 20 and the deformation and crack of two side walls of the slot 204 are formed due to bearing the two side walls of the slot 204 in log-term use. Therefore, the projectile is not secured in the slot 204, and the resonance resulting from the deformation and crack of two side walls of the slot 204 after shooting is generated and louder. It is not acceptable for users. The sense of hearing will be influenced and make user emotionally unstable.
If the bow rod 20 is made by metal materials in order to prevent the bow rod 20 from cracking, the bow rod 20 is too heavy and the cost and price will be very high.
In view of the foregoing circumstances, the inventor has invested a lot of time to study the relevant knowledge, compare the pros and cons, research and develop related products. After quite many experiments and tests, the “crossbow device” of this invention is eventually launched to improve the foregoing shortcomings, to meet the public use.